The Four-Faced Liar (2010)

Shortly after moving in together, Molly and Greg go out for a drink at a local bar, The Four-Faced Liar.  There, they bump into a college classmate of Molly's named Trip.  He introduces them to his girlfriend Chloe, and to his flatmate Bridget, an out and proud lesbian.

Greg and Trip quickly bond, and - initially because she doesn't have anyone else to talk to, and later because they begin to discover shared interests and values - Molly starts spending more and more time with Bridget.  You can probably see where this is heading, even before I mention that Greg and Molly's relationship begins to founder as living together exposes differences and issues that they never previously noticed.

The above probably makes The Four-Faced Liar sound like a very standard coming out relationship story.  And honestly, if you just look at the bare bones of the plot, that's exactly what it is.  But a film doesn't have to break new narrative ground to be well-executed and effective.  This is well-cast, well-acted, and consistently entertaining.  If you're looking for a quiet night in with a queer-friendly romance, you could definitely do a lot worse.